If the TV series "CSI" had an episode about birds, the star could be Pepper Trail. As an ornithologist with the U.S. Fish & Wildlife Service Forensics Laboratory in Ashland, Trail is often called upon to perform autopsies on birds.

If the TV series "CSI" had an episode about birds, the star could be Pepper Trail. As an ornithologist with the U.S. Fish & Wildlife Service Forensics Laboratory in Ashland, Trail is often called upon to perform autopsies on birds.

His most recent cases include oily carcasses from the Gulf of Mexico, where the Deepwater Horizon oil spill killed thousands of birds.

"The main focus of the birds from the Gulf is the cause of death determination," says Trail. "In any investigative circumstance, the cause of death could be anything. We could find a pelican that was shot that has oil on it."

For legal reasons, Trail can't comment on the ongoing cases from the Gulf.

He points to the 1989 Exxon Valdez oil spill as an indication of the results he may find in the aftermath of the Gulf spill.

"In the Exxon Valdez spill, common causes of death for birds included hypothermia; drowning — because they lose their waterproofing and they can't fly and drown; direct toxicity — if they swallow a lot of oil, they can get respiratory problems (or) if they inhale oil, starvation if they can't effectively forage," Trail explains.

Species identification is another critical part of Trail's work, especially when the bird carcass is covered in oil. A human-caused death of a protected species triggers the legal authority for the Fish & Wildlife Service to perform forensic analysis.

"The MBTA (Migratory Bird Treaty Act) protects all native North American migratory bird species except for the members of the game-bird group — the partridges and grouses — that are protected by state game laws," Trail explains.

So when Trail receives a dead oily bird in an overnight mail package, his first task is to determine its species.

Trail stores his specimens in an industrial-size, walk-in freezer. Small birds are stored in marked Ziplock quart-size freezer bags. Before he begins his analysis, Trail turns on the ventilation system to protect himself from the strong chemicals used.

Trail leans over a stainless-steel tray filled with Stoddard Solvent, a liquid that smells like carburetor cleaner. He pinches a black feather in his tweezers and swishes it in the tray. It emerges clean and ready for identification.

Most of the birds Trail cleans in this way come from land-based oil pits rather than from ocean oil spills.

"Birds that come in from the oil pits have typically been in there a while. They're often decomposed; sometimes it's not even recognizable, particularly as a bird. The birds that come from the Gulf are generally still recognizable as birds, so the cleaning process doesn't need to be as extensive," says Trail.

Open oil pits are used to store the byproducts of oil and gas exploration. In 2006, Trail published an article in the journal Environmental Management, in which he estimated that between 500,000 and 1 million birds die every year as a result of these exposed oil pits.

Trail takes the cleaned feather to his desk where he attempts to make a visual match with a feather stored in a computerized database he helped create. "The Feather Atlas" has been available to the public on a website since 2007.

"The primary impetus for creating it was to have a resource for our Fish and Wildlife agents and inspectors so they would have reference material available to them," says Trail.

Bird-watchers around the world have embraced the atlas. According to Trail, the website received 2.6 million hits in the year ending Sept. 30. The site features photos from 172 species, and it is continually updated.

Many pictures for a single species appear in the atlas because feathers come in many varieties.

"We have a lot of pictures of golden eagle feathers because they change their appearance as they age," says Trail. There are differences between males and females, too.

Feathers also vary according to the position on the body — outer or inner wing or tail, for example.

Trail stores all the feathers, along with skeletons and complete bird specimens, in long, low drawers in filing cabinets in a special room. Each specimen in this room serves as a reference against which he can compare his incoming forensic evidence.

He opens a cabinet and pulls out a well-preserved brown pelican, one of the species experiencing high mortality in the BP oil spill. A strong odor of death bursts from the drawer.

"The seabirds — it's not so much the pelicans, but the albatrosses and related birds — have a very distinct, strong, musty smell. Open the parrot drawer and they smell sweet. So an experienced bird man can tell what cabinet he's in — even blindfolded — by the smell," says Trail.

Skulls are used for identification when the birds are so badly decomposed that the feathers are unusable.

"We keep boxes of skeletons that we clean in our bug colony "… we have these flesh-eating beetles that clean the flesh off of bones," Trail explains.

For a lifelong bird-watcher like Trail, forensics presents an emotional challenge. To counter this, he spends his vacation time on natural-history trips in areas rich in bird life.

"Going out and seeing abundance of life and immersing myself in that is psychologically refreshing for me because everything we see here, day in and day out, is just really dead," says Trail. "The spectacle of nature continues.

"It is important to get out and see it."

To view the Fish & Wildlife Service's "Feather Atlas," visit www.lab.fws.gov/featheratlas/index.php.

Daniel Newberry is a freelance writer living in the Applegate Valley. Reach him at dnewberry@jeffnet.org